HST Calibration Reference Data System (CRDS)

 

NOTICE

The term "operational" has changed to "latest" when referring to the newest CRDS Context available. For more information, please refer to the user guide.

Documentation updates are ongoing. If something in the user guide is ambiguous, please reach out to the CRDS team or file a help desk ticket.


 

Obtain Best Reference Files

  1. Using the Command Line
  2. From Dataset ID or FITS Header Upload
  3. Exploring with Instrument Parameters

Reference File Database Services

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  2. Browse Database
  3. Recent Activity

Latest References (under context hst_1358.pmap)

acs

hst_acs_0576.imap      Toggle N/A


atodtab ---- Analog To Digital Lookup Table

biasfile ---- Bias Frame

bpixtab ---- Data Quality (Bad Pixel) Initialization Table

ccdtab ---- Ccd Parameters Table

cfltfile ---- Coronagraphic Spot Flat Image

crrejtab ---- Cosmic Ray Rejection Parameter Table

d2imfile ---- Column Correction File

darkfile ---- Dark Frame

dgeofile ---- Geometric Distortion Correction File

drkcfile ---- Cte Corrected Dark

flshfile ---- Post-flash Image

idctab ---- Image Distortion Correction File

imphttab ---- Photometry Keyword Table

mdriztab ---- Multidrizzle Parameter Table

mlintab ---- Mama Linearity Table

npolfile ---- Non-polynomial Offset

oscntab ---- Overscan Region Table

pctetab ---- Pixel CTE Correction Table

pfltfile ---- Pixel To Pixel Flat Field Image

satufile ---- Full-Well Saturation Level Map

shadfile ---- Shutter Shading Correction Image

snkcfile ---- Sink Pixel Correction Image

spottab ---- Spot Position Table

cos

hst_cos_0385.imap      Toggle N/A


badttab ---- Bad Time Interval Table

bpixtab ---- Data Quality (Bad Pixel) Initialization Table

brftab ---- Baseline Reference Frame Table

brsttab ---- Burst Parameters Table

deadtab ---- Deadtime Reference Table

dgeofile ---- Geometric Distortion Correction File

disptab ---- Dispersion Relation Table

flatfile ---- Flat Field

fluxtab ---- Sensitivity Reference Files

geofile ---- Geometric Distortion Correction

gsagtab ---- Gain Sag Reference Table

hvdstab ---- Reference file that contains the slopes, y intercepts, and zero points of a high voltage-dependent sensitivity correction for COS FUV

hvtab ---- High Voltage Reference Table

lamptab ---- Template Calibration Lamp Spectra Table

phatab ---- Pulse Height Parameters Table

proftab ---- 2D Spectrum Profile Table

spottab ---- Spot Position Table

spwcstab ---- Spectroscopic WCS Parameters Table

tdstab ---- Time Dependent Sensitivity Table

tracetab ---- 1D Spectral Trace Table

twozxtab ---- Two-Zone Spectral Extraction Parameters Table

wcptab ---- Wavecal Parameters Reference Table

xtractab ---- 1-d Extraction Parameters Table

xwlkfile ---- X Walk Correction Lookup Reference Image

ywlkfile ---- Y Walk Correction Lookup Reference Image

nicmos

hst_nicmos_0250.imap      Toggle N/A


darkfile ---- Dark Frame

flatfile ---- Flat Field

idctab ---- Image Distortion Correction File

illmfile ---- Illumination Pattern File

maskfile ---- Static Mask File

nlinfile ---- Detector Linearity Correction File

noisfile ---- Detector Read-noise File

pedsbtab ---- pedsbtab

phottab ---- Phototmetric Calibration Table

pmodfile ---- Persistence Model Files

pmskfile ---- Persistence Mask Files

rnlcortb ---- Nonlinearity Power Law Table

saacntab ---- SAACLEAN Task Parameters

saadfile ---- Post Saa Dark Assoc.

tdffile ---- Temperature Dependent Flat Fields

tempfile ---- Temperature-dependent Dark Reference File

zprattab ---- Nonlincor Zeropoint Scaling Table

stis

hst_stis_0404.imap      Toggle N/A


apdestab ---- Aperture Description Table

apertab ---- Aperture Throughput Table

biasfile ---- Bias Frame

bpixtab ---- Data Quality (Bad Pixel) Initialization Table

ccdtab ---- Ccd Parameters Table

cdstab ---- Cross-disperser Scattering Table

crrejtab ---- Cosmic Ray Rejection Parameter Table

darkfile ---- Dark Frame

disptab ---- Dispersion Relation Table

echsctab ---- Echelle Scattering Table

exstab ---- Echelle Cross-Dispersion Scattering Table

gactab ---- Grating-Aperture Correction Table

halotab ---- Detector Halo Table

idctab ---- Image Distortion Correction File

imphttab ---- Photometry Keyword Table

inangtab ---- Incidence Angle Correction Table

lamptab ---- Template Calibration Lamp Spectra Table

lfltfile ---- Low-order Flat Field Image

mlintab ---- Mama Linearity Table

mofftab ---- Mama Offset Correction Table

pctab ---- Photometric Correction Table

pfltfile ---- Pixel To Pixel Flat Field Image

phottab ---- Phototmetric Calibration Table

riptab ---- Echelle Ripple Table

sdctab ---- 2-d Spectrum Distortion Corrections

sptrctab ---- 1-d Spectrum Trace Table

srwtab ---- Scattering Reference Wavelength Table

tdctab ---- Nuv Dark Correction Table

tdstab ---- Time Dependent Sensitivity Table

teltab ---- Telescope Point Spread Function Table

wcptab ---- Wavecal Parameters Reference Table

xtractab ---- 1-d Extraction Parameters Table

synphot

hst_synphot_0082.imap      Toggle N/A


obsmodes ---- Observing Modes Table

thermal ---- Component Thermal Tables

thruput ---- Component Throughput Tables

tmctab ---- Master Component Lookup Table

tmgtab ---- Graph Table

tmttab ---- Thermal Component Lookup Table

wfc3

hst_wfc3_0660.imap      Toggle N/A


atodtab ---- Analog To Digital Lookup Table

biacfile ---- CTE Bias Frame

biasfile ---- Bias Frame

bpixtab ---- Data Quality (Bad Pixel) Initialization Table

ccdtab ---- Ccd Parameters Table

crrejtab ---- Cosmic Ray Rejection Parameter Table

d2imfile ---- Column Correction File

darkfile ---- Dark Frame

dfltfile ---- Delta Flat Field Image

drkcfile ---- Cte Corrected Dark

flshfile ---- Post-flash Image

idctab ---- Image Distortion Correction File

imphttab ---- Photometry Keyword Table

mdriztab ---- Multidrizzle Parameter Table

nlinfile ---- Detector Linearity Correction File

npolfile ---- Non-polynomial Offset

oscntab ---- Overscan Region Table

pctetab ---- Pixel CTE Correction Table

pfltfile ---- Pixel To Pixel Flat Field Image

satufile ---- Full-Well Saturation Level Map

snkcfile ---- Sink Pixel Correction Image

wfpc2

hst_wfpc2_0250.imap      Toggle N/A


atodfile ---- Analog To Digital Converter Lookup Table

biasfile ---- Bias Frame

darkfile ---- Dark Frame

dgeofile ---- Geometric Distortion Correction File

flatfile ---- Flat Field

idctab ---- Image Distortion Correction File

maskfile ---- Static Mask File

offtab ---- Inter-chip Offsets Table

shadfile ---- Shutter Shading Correction Image

wf4tfile ---- WF4 Correction Table


Context History (more history, all contexts, build contexts)

Start Date Context Status Description
2026-09-16 hst_1358.pmap latest New WFC3 UVIS bad pixel and dark calibration reference files have been created using Cycle 33 monitoring and calibration data obtained between July 21 and August 22, 2026 for programs 17944, 17947, and 17948. These files extend beyond the most recent reference files currently available in CRDS, which only include bad pixel tables through June 23, 2026 and dark reference files through July 13, 2026. The new bad pixel table, with a USEAFTER date of July 21, 2026, should be applied to all UVIS observations from July 21, 2026 onward, while the new superdark drk/dkc reference files should be used for UVIS data obtained between July 21 and August 19, 2026. Together, these reference files provide the most accurate representation of detector behavior, including pixel stability, dark current, and hot pixels, for observations taken during this period. The bad pixel tables were generated from 900-second dark exposures, and the dark reference files were produced from Cycle 33 calibration dark exposures. Additional details on the generation methods can be found in WFC3 ISRs 2018.15, 2021.14, and 2016-08, as well as in the HISTORY sections of the reference file headers.
2026-09-02 hst_1356.pmap archived Delivery of new STIS CCD bias and dark reference files for CCD data taken between August 04 2026 through September 01 2026. The files were generated from data taken in the same time frame under STIS calibration programs 18158, and 18156.
2026-09-01 hst_1355.pmap archived The ACS WFC bias, dark, CTE dark, and sink files were generated following the ACS WFC anneal on August 28, 2026, and should be used to calibrate ACS WFC observations taken between July 27, 2026 and August 28, 2026.
2026-08-27 hst_1354.pmap archived Delivered a new COS FUV WCPTAB reference file because we analyzed historical data using a new MCMC parameter estimate and updated the split wavecal parameters, which had previously been calculated with a less accurate technique. We also delivered an updated COS WCPTAB rmap that manually replaces the old file, 9812020ol_wcp.fits, with its replacement, a8r1605il_wcp.fits. This new WCPTAB will cover FUV data for lifetime positions -1.0, 6.0, and 7.0.